After they invaded Mexico in the early sixteenth century, Spanish conquistadores took advantage of indigenous copper-smelting technology to produce weapons that helped them solidify their dominion over Mesoamerica. Smelting technology had arrived in Mesoamerica from the Andes and northern coastal South America beginning around A.D. 700. Historical records show that the Spanish wanted to construct cannons out of bronze—an alloy of copper and tin. However, the invaders did not know how to smelt copper ore and were forced to negotiate with indigenous specialists to obtain it. New research at the site of El Manchon in the Mexican state of Guerrero suggests that members of a community there smelted copper both before and after the Spanish invasion. Archaeological evidence includes the remains of furnaces, mounds of copper slag, and copper ore. “The community likely used traditional blowpipe furnaces to begin producing copper ingots, which may then have been fashioned into prestige or ritual items,” says archaeologist Dorothy Hosler of the Massachusetts Institute of Technology. While the Spanish exploited the community’s smelting resources, they also appear to have introduced European-style bellows, which led to a new hybrid furnace design that was used to produce the great quantities of copper required to make weapons and artillery.
